LAS VEGAS -- Former two-division titleholder Timothy Bradley Jr. and Jessie Vargas, a secondary junior welterweight titleholder, will square off in a 12-round welterweight fight on June 27 at the StubHub Center in Carson, California.

Vargas will rise in weight to take on Bradley in the HBO-televised main event.

"You better train hard. We got to put on a good show for the fans," Bradley told Vargas as they shook hands when they were ringside for the Raymundo Beltran-Takahiro Ao card this past Friday night. "I don't want no excuses."

Jessie Vargas, left, will move up from junior welterweight to fight Timothy Bradley Jr. in a welterweight fight on June 27. Ed Mulholland/HBO

Bradley (31-1-1, 12 KOs), 31, of Palm Springs, California, is a former junior welterweight and welterweight titlist looking to get back on track. Since an impressive performance in a split decision win against Mexican star Juan Manuel Marquez in October 2013, Bradley is 0-1-1.

Bradley lost a lopsided decision to Manny Pacquiao in their April 2014 welterweight title rematch after having gotten a highly controversial split decision win against Pacquiao in June 2012. In December, Bradley was held to a split draw against Diego Chaves in a fight most ringside observers thought Bradley clearly won.

"Vargas is a good, little fighter," Bradley told ESPN.com. "He's a world champion, and he has to be respected. This is another good fight, another good opponent. I'm always fighting good competition. He's undefeated. I think this is a good test for both of us and a good fight for me against an undefeated fighter."

Bradley was in position to face former welterweight titleholder Shawn Porter in a title elimination fight in which the victor would have become the mandatory challenger for titleholder Kell Brook. However, Bradley and promoter Top Rank, which has a horrible relationship with Porter adviser Al Haymon, decided to go in another direction, and the Bradley-Porter purse bid was canceled.

Vargas (26-0, 9 KOs), 25, of Las Vegas, claimed a secondary belt in April 2012 on the Pacquiao-Bradley II undercard by narrowly outpointing Khabib Allakhverdiev. Vargas defended the belt twice last year, outpointing unbeaten Anton Novikov in August and former lightweight titleholder Antonio DeMarco in November.

"I'm very excited about this fight," Vargas told ESPN.com. "I'm extremely excited to be getting the opportunity to fight a name like Timothy Bradley, a guy who beat Manny Pacquiao. I know it was controversial, but he has a win over him. I'm trying to get closer to fighting the big names."

Vargas, who has had several bouts as a welterweight, has not yet vacated his 140-pound belt but said it was time for him to move back up to 147.

"It was getting harder for me to make 140. I knew it was coming to an end, and I didn't want to get to a point where that last half-pound would hurt me," said Vargas, who is trained by former pound-for-pound king Roy Jones Jr. "I'm looking forward to fighting at 147. I was successful in past fights at 147."

The fight has a chance to be exciting. Bradley outpointed Ruslan Provodnikov in the 2013 fight of the year, and Vargas' fights have been more fan-friendly of late than earlier in his career.

"Tim is a great fighter, and that's why I'm excited. We both come to fight and give the fans a great fight," Vargas said. "Timmy always comes and gives an exciting fight. I want to be a fan-friendly fighter."

Said Carl Moretti, vice president of Top Rank, "Because of their styles, I think it's going to be a great fight and the winner is going to come out as a big player in the division. Jessie wanted to move to 147 and he's been on HBO before. Any time you get a good fight in the welterweight division, there's interest, and this is a good fight in the welterweight division.

"It's a fight that keeps Bradley going in another competitive fight, and for Jessie, it's a chance for him to fight a big name. Jessie is sky-high for the fight."

Although Bradley has faced several opponents with much bigger names than Vargas -- Pacquiao twice, Marquez, Provodnikov, Devon Alexander and Lamont Peterson, to name a few -- he said he would not overlook Vargas.

"It ain't hard to get up for this fight," he said. "He wants what I got. He wants my name on his resume. You got to get in there and show me you can beat me. I've faced big names in the sport, but I'm [a] risk-taker, baby. It's me and him that night."

The HBO co-feature has not yet been determined. Moretti said that lightweight contender Diego Magdaleno (27-1, 11 KOs), 28, of Las Vegas, would appear on the undercard against an opponent to be determined. Magdaleno has won four fights in a row since suffering his lone defeat, a split decision in Macau, China, in which he challenged Roman "Rocky" Martinez for a junior lightweight world title in April 2013.